3 files changed, 45 insertions, 8 deletions

diff --git a/fs/lockd/svc4proc.c b/fs/lockd/svc4proc.c
index 50ee8eb139ab..014f6ce48172 100644
--- a/fs/lockd/svc4proc.c
+++ b/fs/lockd/svc4proc.c
@@ -421,11 +421,9 @@ nlm4svc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
 {
         struct sockaddr_in      saddr;
 
-        memcpy(&saddr, svc_addr_in(rqstp), sizeof(saddr));
-
         dprintk("lockd: SM_NOTIFY     called\n");
-        if (saddr.sin_addr.s_addr != htonl(INADDR_LOOPBACK)
-         || ntohs(saddr.sin_port) >= 1024) {
+
+        if (!nlm_privileged_requester(rqstp)) {
                 char buf[RPC_MAX_ADDRBUFLEN];
                 printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
                                 svc_print_addr(rqstp, buf, sizeof(buf)));
diff --git a/fs/lockd/svcproc.c b/fs/lockd/svcproc.c
index 935ce967a6a1..548b0bb2b84d 100644
--- a/fs/lockd/svcproc.c
+++ b/fs/lockd/svcproc.c
@@ -453,11 +453,9 @@ nlmsvc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
 {
         struct sockaddr_in      saddr;
 
-        memcpy(&saddr, svc_addr_in(rqstp), sizeof(saddr));
-
         dprintk("lockd: SM_NOTIFY     called\n");
-        if (saddr.sin_addr.s_addr != htonl(INADDR_LOOPBACK)
-         || ntohs(saddr.sin_port) >= 1024) {
+
+        if (!nlm_privileged_requester(rqstp)) {
                 char buf[RPC_MAX_ADDRBUFLEN];
                 printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
                                 svc_print_addr(rqstp, buf, sizeof(buf)));
diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h
index e6b070979287..b56d5aa9b194 100644
--- a/include/linux/lockd/lockd.h
+++ b/include/linux/lockd/lockd.h
@@ -277,6 +277,47 @@ static inline struct inode *nlmsvc_file_inode(struct nlm_file *file)
         return file->f_file->f_path.dentry->d_inode;
 }
 
+static inline int __nlm_privileged_request4(const struct sockaddr *sap)
+{
+        const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
+        return (sin->sin_addr.s_addr == htonl(INADDR_LOOPBACK)) &&
+                        (ntohs(sin->sin_port) < 1024);
+}
+
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+static inline int __nlm_privileged_request6(const struct sockaddr *sap)
+{
+        const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
+        return (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LOOPBACK) &&
+                        (ntohs(sin6->sin6_port) < 1024);
+}
+#else   /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
+static inline int __nlm_privileged_request6(const struct sockaddr *sap)
+{
+        return 0;
+}
+#endif  /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
+
+/*
+ * Ensure incoming requests are from local privileged callers.
+ *
+ * Return TRUE if sender is local and is connecting via a privileged port;
+ * otherwise return FALSE.
+ */
+static inline int nlm_privileged_requester(const struct svc_rqst *rqstp)
+{
+        const struct sockaddr *sap = svc_addr(rqstp);
+
+        switch (sap->sa_family) {
+        case AF_INET:
+                return __nlm_privileged_request4(sap);
+        case AF_INET6:
+                return __nlm_privileged_request6(sap);
+        default:
+                return 0;
+        }
+}
+
 static inline int __nlm_cmp_addr4(const struct sockaddr *sap1,
                                   const struct sockaddr *sap2)
 {